Patterns of adventitious root induction during different seasons in some bamboo species Sanjay Singh * , N. P. S. Nain, S. L. Meena and S. P. Tripathi Tropical Forest Research Institute, P. O. RFRC, Jabalpur 482021, India Abstract: The influence of seasons and auxin /non-auxin growth regulators on adventitious root formation was examined to evolve cloning procedures for Bambusa multiplex, B. tulda, B. vulgaris and Dendrocalamus membranaceus. During three growing seasons (winter, summer and rainy), single-node culm cuttings were prepared from mature culms and treated for 24 h with 2 mM indole-3-acetic acid (IAA), indole-3-butyric acid (IBA), naphthalene acetic acid (NAA), boric acid and water (control) separately. The treated cuttings were horizontally placed, covered completely with sand and maintained for 2 months in low-cost mist chamber. The best rooting occurred in summer season, which was enhanced by 56.5 per cent and 19.4 per cent over that in winter and rainy seasons, respectively. In general, the potential of different bamboo species for adventitious rhizogenesis was found to be in the order: B. vulgaris > B. multiplex > D. membranaceus > B. tulda. The treatment with boric acid, NAA and IBA resulted in significantly increased overall adventitious rooting than water treated control but at the individual species level, growth regulators (IBA and NAA) significantly enhanced adventitious rhizogenesis only in B. tulda. Key words: Adventitious rhizogenesis, Bambusa tulda, Bambusa multiplex, boric acid, growth regulators. INTRODUCTION Vegetative propagation of bamboos involves various procedures, most of which aim at transforming the innumerable buds present at every node into planting material (Banik, 1980). Among these procedures, propagation through adventitious rhizogenesis of culm/branch cuttings is a viable option having the advantage of obtaining enormous number of cuttings from a clump and low costs of transport, handling and labour (Dransfield and Widjaja, 1995). The method of rooting of cuttings has been adopted for propagation of bamboos since long (Pathak, 1899; Dabral, 1950; McClure, 1966). However, bamboo species exhibit significant variation in the capability of adventitious rhizogenesis, some rooting with * To whom correspondence should be addressed; E.mail: sanjaysingh@lycos.com J. Bamboo and Rattan, Vol.5, Nos. 1&2, pp. 101-107 (2006)  KFRI 2006